Ballasts provided with built-in thermal protection are listed by UL as Class P ballasts . Under normal conditions, the Class P ballast has a case temperature not exceeding 194°F (90°C). The thermal protector must open within 2 hours when the case temperature reaches 230°F (110°C).
What is a Class P type ballast?
Class P: A ballast for a fluorescent lamp which meets the requirements of the Underwriters’ Laboratories, Inc.; includes an automatic resetting thermal protector to remove the ballast from the circuit if its temperature exceeds a specified value.
What are the four basic types of fluorescent ballasts?
Fluorescent Tube Diameters
The most common types are T12, T8, and T5 . The T stands for tubular and the number indicates the diameter in 1/8 of an inch. Lamp diameter is determined by ballast type. A fixture with a T12 ballast must use a T12 bulb.
What is one type of protection for fluorescent ballasts?
Currently, the protective measures for electronic ballasts are: Connect a single-use current fuse to the input of the ac-circuit . Ballast designers may believe that connecting a current fuse at this position will protect the ballast from overcurrent or abnormal states.
Which type of ballast has the highest system efficiency?
The most efficient ballasts are electronic, or high-frequency ballasts . These typically boost the frequency of the electricity from 60 cycles per second (hertz) to between 25,000 to 40,000 hz. At the higher frequency, the fluorescent lamps are more efficiently excited.
Do you need an electrician to change a ballast?
Yes. As a matter of fact, you do need a lock out tag out device in place for changing a ballast. ... ‘ An electrician is replacing the ballast on a fluorescent light . The electrician uses the light switch on the wall to de-energize the florescent light.
How much does it cost to replace a ballast?
The average cost of ballast replacement is $150 for materials and labor. Materials cost an average of $27.50, and labor costs at least $100 to install a ballast replacement. Homeowners often spend $35 per ballast for programmed-start ballast installation and labor.
How long do electronic ballasts last?
According to the Certified Ballast Manufacturers Association, the average magnetic ballast lasts about 75,000 hours, or 12 to 15 years with normal use. The optimum economic life of a fluorescent lighting system with magnetic ballasts is usually about 15 years.
What happens if you wire a ballast wrong?
If the ballast is bad, then the needle won’t move . If you’re using a digital multimeter, often the digital readout will possibly list a “1” when it doesn’t find a measurable resistance.
What is inside a ballast?
A magnetic ballast (also called a choke) contains a coil of copper wire . The magnetic field produced by the wire traps most of the current so only the right amount gets through to the fluorescent light. That amount can fluctuate depending on the thickness and length of the copper wire.
Can a fluorescent light work without a ballast?
In a fluorescent lighting system, the ballast regulates the current to the lamps and provides sufficient voltage to start the lamps. Without a ballast to limit its current, a fluorescent lamp connected directly to a high voltage power source would rapidly and uncontrollably increase its current draw.
Are ballasts worth scrapping?
The worst type of ballast that you can have is a PCB ballast. These are very harmful to the environment and many scrap yards will not want to buy or even take these in as as scrap because they are very difficult to recycle correctly.
Are all ballast the same?
And there are two types of ballasts in each family: magnetic and electronic . Magnetic ballasts are the older ballast technology. For the fluorescent family, both T12 linear fluorescents and two-pin CFLs use magnetic ballasts. ... Today, most fluorescent and HID lamps operate off an electronic ballast.
What’s the difference between rapid start and instant start ballast?
Rapid start configurations have two wires connected to each side of the lamp. There is a small voltage between the two wires that is used to provide heat to the lamp’s cathodes. ... With an instant start configuration, a high voltage pulse is used to start the arc between the lamp’s cathodes.
Which ballast has the highest power factor?
usually have a power factor below 1.0. Normal power factor ballasts (NPF) typically have a value of (0.4) – (0.6). Ballasts with a power factor greater than (0.9) are considered high power factor ballasts (HPF).
